Cleaning putty off glass after single glazing

[Modernista]

Probably a silly question but seeing how good-natured you folks are I will ask anyway - I've just single-glazed a small internal borrowed light with beads and linseed oil back putty - am I ok leaving the final clean off of putty at the edges until after the back putty has hardened? When I try and do it now I keep catching the exposed edge of putty - but just worried if I leave it until the putty is hard I will struggle to remove the smear round the edge and I don't want to resort to scraping/scratching (or live with a smeary edge!). Maybe just white spirit or something later?